This invention relates to welding polymers. More particularly, this invention relates to welding resinous block copolymers containing antiblocking agent.
Solvent welding of thermoplastic resinous polymers has been known for some time utilizing such solvents as methylene chloride, methyl ethyl ketone, perchloroethylene, and 1,1-dichloroethane. However, these solvents suffer from one or more disadvantages such as toxicity, expense and the promotion of stress cracking in the welded polymer.
These solvents impose an additional problem when used to bond resinous block copolymers containing an antiblock agent such as a microcrystalline wax as disclosed in U.S. Pat. No. 3,766,114, the disclosure of which is incorporated herein by reference. With this type of block copolymer that contains an antiblock agent the usual solvent materials employed for solvent welding cause serious problems because the solvent materials dissolve the wax as well as soften or dissolve the polymer. This dissolved wax tends to remain sticky or tacky for extended periods of time at the surface, thus causing difficulties in handling the solvent welded articles.